Battery Energy Storage Explained

This type of energy solution is fast becoming a necessity to ensure reliable, low-carbon electricity.

By 2030, the government aims to reduce greenhouse gas emissions by a whopping 68%. This involves new guidelines on electric cars and other vehicles, as well as a commitment to clean power.

Additonally, by 2030 the UK aims to generate a staggering 95% of the country’s electricity from clean sources, representing a significant increase from the 42% produced today.

Renewable energy, including solar, wind and hydropower, is expected to meet this electricity demand, and solar panels in particular are becoming increasingly popular for homeowners and businesses as a source of prime power. But the transition to sustainable power is not without its difficulties.

One of the most challenging aspects is the variable nature of sources like solar and wind due to environmental conditions. This type of energy is dependent on the weather, making its output unpredictable and not always available, which has a knock-on effect on the stability of the power grid.

Battery Energy Storage Systems (BESSs) are bridging the gap between intermittent renewables and constant demand. By storing surplus energy and releasing it when needed, we can maintain a consistent power flow and reduce our reliance on fossil fuels.

How Do Battery Energy Storage Systems Work?

Battery energy storage is a technology that allows electricity to be stored in rechargeable batteries and used later. It’s a similar process to the daily charging of our mobile phones. When electricity supply exceeds demand, BESS charges by storing the energy in its batteries. When demand is high or renewable energy generation is low, BESS releases stored energy back to the grid.

This all sounds simple enough, but let’s delve into the details for a clear picture of what exactly happens during the process.

Key Components

• Battery Banks / Cells – the core of the system, where the energy is stored. Lithium-ion batteries are the most common due to their high energy density and efficiency. Other types include lead-acid and flow batteries. Each battery cell has a fixed capacity – the larger the battery, the more electricity it can store.
• Bidirectional Inverter – an electronic device that can convert electricity in both directions, to charge the battery with electricity and discharge it back to the grid. Batteries store energy as DC current, and power grids and appliances use AC. An inverter converts the electricity into the appropriate current.
• Energy Management System – plays a vital role in regulating and controlling the flow of electricity. It is a piece of software or platform that acts as a decision-maker, using real-time data to determine when to charge, when to discharge, and how to interact with the grid, renewables, or local loads. Effective use of an EMS maximises energy through peak shaving and extends battery life by avoiding harmful deep cycles or overheating.
• Thermal Management – a set of rules used to maintain batteries within their safe operating temperature range. Temperature sensors and cooling units prevent overheating, keep the battery running at optimal performance and slow down battery cell degradation. There are several cooling methods, including air and liquid cooling.
• Control System – a multi-layer system to manage power flow, safety operations, system coordination and communicate with the grid, renewables and loads. A control system will include emergency stop functions, fault detection and automatic shutdown in case of fire or other hazards. It ensures safe operation and smooth energy conversion by integrating with the BMS, inverter, EMS, and thermal management process.

How It Works

BESS receives energy from the grid or renewables
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Bidirectional inverter converts AC electricity into DC
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Battery cells store the energy chemically
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Thermal management system keeps batteries at the right temperature
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EMS decides when to discharge energy
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Bidirectional inverter converts DC to AC and discharges stored energy

 

Technologies like BESS are supporting the UK energy system and could save the UK energy system up to £40 billion by 2050, ultimately reducing people’s energy bills.

Using Battery Storage with Solar Panels and Power Generators

A battery energy storage system can be effectively combined with solar power and a diesel or petrol generator to create a reliable and efficient hybrid energy system. Investing in solar panels is an excellent choice for businesses wanting to use sustainable energy while reducing their reliance on the grid.

Solar PV technology uses the sun to generate electricity, providing a low-carbon solution to power office buildings, warehouses and other industrial and commercial settings.

Battery energy storage supported by a generator can bridge the power gap when energy from the sun is low. BESS can store surplus energy when output is high, feeding it back to the system when energy is low. During extended power outages, using a generator alongside BESS means the batteries can be recharged when they run low.

A diesel generator provides an extra layer of energy security to keep your operations running smoothly.

Balancing renewable energy with stored energy and conventional backup ensures reliability and delivers significant cost savings. Explore the range of commercial solar panels, battery storage systems and diesel generators at Vital Power, your industry-leading power solution provider.